Passive smoking means that people who live and work around smokers unconsciously inhale smoke and dust particles and various toxic substances. The concentration of harmful substances inhaled by passive smokers is not lower than that of smokers, and the cold smoke exhaled by smokers contains one times more tar, two times more benzopyrene, and four times more carbon monoxide than the hot smoke inhaled by smokers. The concentration of harmful substances in the smoke inhaled is not lower than that of smokers, and studies have shown that smokers exhale cold smoke in which the tar content is 1 times more than that in hot smoke inhaled by smokers, 2 times more benzopyrene, and 4 times more carbon monoxide. Foreign data show that wives of husbands who smoke (passive smokers) have 2 times more lung cancer than non-smokers. The risk of lung cancer increases with the amount of smoking by the husband. Some scholars have also analyzed more than 5,000 pregnant women and found that when the husband smokes more than 10 cigarettes a day, the prenatal mortality rate of his fetus increases by 65%; the number of respiratory diseases in children of smoking families is much higher than in non-smoking families. It can be said that one person who smokes, affects everyone.